Almost $800,000 in penalties have been paid out by Australian energy provider AGL after it allegedly failed to provide customers with correct best offer advice.
Victoria's independent economic regulator accused AGL of failing to calculate its "deemed best offer" check in line with a prescribed formula for 22 customers from March to June 2022.
An energy retailer's deemed best offer is its cheapest generally available offer and based on customer power usage over the past year.
It does not include one-off gifts or sign-up credits.
Retailers must regularly inform Victorian customers through their electricity and gas bills if they are on their best offer, as well as how they could save by switching.
The Essential Services Commission gathered evidence showing AGL's alleged calculation errors deprived the 22 customers of accurate best offer information and reported the issue to the company.
Commissioner Sitesh Bhojani said non-compliance with best offer rules was serious.
"The fact this issue was only identified following proactive inquiries from the commission indicates that aspects of AGL's best offer compliance system were inadequate," he said in a statement on Friday.
"Retailers that do not comply with their obligations under the best offer rules undermine the intended consumer benefits of these provisions, as well as consumer trust in energy businesses more generally."
Commissioner Bhojani said best offer information was even more important as many Victorians faced increased cost-of-living pressures.
"This is the second time in as many months that the commission has held an energy business to account for depriving customers of critical best offer information they are entitled to," he said.
In September, Red Energy paid $254,436 in fines after allegedly breaching customer best offer information rules.
Another $73,958 in penalties was separately paid by AGL last month over the alleged wrongful disconnection of a customer experiencing difficulty paying power bills.